This invention relates to an integrated assay system, more specifically, to assessing the effectiveness of a drug and the organ function of a patient by measuring the concentrations of an organ marker, a drug and/or one or more metabolites with an integrated test system.
Many drugs are currently available to treat diseases such as diabetes mellitus, cancer, hypertension, seizure disorders and infection. However, a number of these drugs can be dangerous and have been shown to result in organ damage in certain patients. On occasion, permanent organ damage can go undetected because potential drug side effects are not monitored effectively. Such organ damage may eventually require an organ transplant or even lead to death.
For example, the drug troglitazone helps diabetes patients to control abnormally high blood glucose levels. Most patients tolerate this drug well and develop no lasting harmful side effects. Others tolerate the drug initially, but suddenly develop liver disease. Fortunately, for most of these patients, organ damage can abate or disappear when the drug is discontinued. However, some patients can develop permanent liver damage, which may result in death or require a transplant, especially if the patient""s liver function is not being monitored regularly. Accordingly, liver function tests are strongly recommended before and periodically during treatment with troglitazone.
Drug-related organ damage is not limited to the liver, since most major organs can be damaged from a number of abnormal physiological conditions. For example, patients taking the drug metformin, which is used mainly to manage diabetes mellitus, can develop kidney dysfunction. Other drugs implicated in conditions leading to organ damage include phenytoin, used for treating seizure disorders, which can lead to liver and kidney damage; methyldopa, for treating hypertension can lead to liver damage; docetaxel, gemutabine, bicalutamide, nilutamide, all of which are used to treat cancer and can lead to liver damage; antibiotics such as streptomycin, which can lead to liver and kidney damage; isoniazid, for treating tuberculosis, which can lead to liver damage; and tolcopone, for treating Parkinson""s disease, which can lead to liver damage. Thus, it is critical to monitor organ function in patients receiving these and other potentially dangerous drugs so that the dosage can be altered or even discontinued at the first indication of organ damage.
Organ function tests alone do not always give a realistic indication of the patient""s overall condition. There are instances where it also would be beneficial to monitor a drug and/or metabolite affected by the drug at the same time as organ function, so that a more accurate diagnosis of the condition can be made. For example, possible organ damage indicated by a reduced organ function assay could be due to a pre-existing underlying condition, rather than the drug therapy itself. In these situations, potentially life-threatening conditions could go undiagnosed. In addition, it would be beneficial to measure the drug concentration and/or metabolite concentration at the same time as organ function to find the optimal dosage of the drug to manage the condition. However, there are no integrated test systems that measure the concentration of organ marker, drug and/or one or more metabolites that are simple and convenient to use by a physician in the office or at home by the patient.
Currently, organ function assays require a venipuncture blood sample and are typically performed in a clinical lab using complicated techniques and expensive instrumentation. Results from these clinical lab tests are usually not available to the doctor and patient for several days. This delay in reporting can decrease the value of the test result. The physician can even neglect to relay the test result to the patient until the next visit, which could be several months later.
Therefore, a need exists for conveniently and quickly measuring concentrations of organ marker, drug and/or one or more metabolites in combination to give a better evaluation of the therapeutic effectiveness of the drug and the well-being of a patient. Currently, no such test system exists. Particularly useful would be an integrated instrument for determining a patient""s overall organ function that could be used at the doctor""s office, or better yet, at home by the patient. The present invention satisfies these needs and provides related advantages as well.
The present invention provides a method for assessing the effectiveness of a drug therapy and the organ function of a patient by measuring the concentration of an organ marker, drug and/or one or more metabolites in a patient""s body fluid. The invention also provides an integrated test system for performing the method of the invention.